Biotic Potential Induced by Different Host Plants in the Fall Armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae)

Simple Summary Fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), is an economically important insect pest of corn crops globally. However, some other host plants on which this pest can successfully complete its generation have also been reported. Our main objective was to study the biology of fall armyworm feeding on maize, sorghum, wheat, and rice. Our overall findings show that maize is the most preferred host plant; however, the pest completed the life cycle successfully on sorghum and wheat. The survival rate was low when rice leaves were provided to larvae as diet, suggesting that rice is a non-preferred host plant. Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a polyphagous insect pest of many important crops. To evaluate the influence of host plants on the biology and survival of the Pakistani population of S. frugiperda, we examined life table parameters of S. frugiperda raised on maize, sorghum, wheat, and rice. The development rate was significantly higher on the maize crop than on the other three host plants. Different larval diets affected development time and fecundity. S. frugiperda attained the fastest larval development (16 days) on maize and the slowest development (32.74 days) on rice. Adult females from maize-fed larvae laid 1088 eggs/female, those from sorghum-fed larvae laid 591.6 eggs/female, those from wheat-fed larvae laid 435.6 eggs/female, and those from rice-fed larvae laid 49.6 eggs/female. Age stage-specific parameters also indicated the higher fecundity, higher life expectancy, and higher survival of S. frugiperda on maize plants than on the other three hosts. Larval diets had a significant varying effect on the finite and intrinsic increase rates, reflecting that maize was the most suitable diet. The findings of the present study are useful for predicting population dynamics especially in areas cultivating Poaceae crops, except maize, to develop sustainable integrated pest management strategies for this pest.

Automated summary

The fall armyworm is a polyphagous insect pest, preferring maize but also able to complete its life cycle on sorghum and wheat. Rice is a non-preferred host plant for fall armyworm. Larval diets significantly impact development time, fecundity, and survival rates of the insect. Maize is found to be the most suitable diet for fall armyworm based on the study's findings.